Ideal for making tough, straight cuts. The Torch metal-cutting blades with the Double Duty upgrade feature a tooth form optimized for the longest life and maximum durability. Tough Neck is engineered to protect against tang breakage and delivers the strongest SAWZALL. Grid Iron features a stamped honeycomb pattern throughout the body of the blade that greatly increases the rigidity of the blade, making it the stiffest metal cutting SAWZALL blade. 1/2" universal shank. For metal 1/4" to 7/16".